It is common in Summer league swimming to swim in a “yards” pool one week, and then in a “meters” pool the next. The vast majority of Summer league swim meets are held in either a 25-yard or 25-meter pool. These course correction factors, if used, are calculated and tracked separately for each pool. This course correction is similar to, but different from, the time conversion used to estimate times between standard pool courses. To account for these variations, sometimes a pool-specific “course correction factor” is calculated and applied to all results recorded in that pool. In some cases, such as 20-yard or 33 ⅓ yard pools, the difference can be very significant. When measured precisely, many neighborhood pools will be a little longer or a little shorter than their specified course. It is not uncommon for recreational pools to not be built to exacting standards. Side note: accounting for imprecise pool lengths And, of course, a 50-meter pool is twice the length of a 25-meter pool. A 25-yard pool is equivalent to 22.86 meters, or a bit more than 90% the length of a 25-meter pool. The key thing to remember about swim courses is that they describe different distances. This course is abbreviated as “LCM” or just “L”. This much larger pool size is rarely used for neighborhood or club pools. This is the pool length used for the Olympics and many international competitions, and during the “long course season” of USA Swimming from April to August.

50 meters - known as “ long course meters” or simply “long course”.This course is abbreviated as “SCM” or just “S”. This pool length is generally used for year-round/club and international competition, and is also used for some neighborhood and country club pools.

25 meters - also known as “ short course meters” or simply “short course” or “meters”.This course is abbreviated as “SCY” or just “Y”. This pool length is frequently used for high school and collegiate competitions, and is also often used for neighborhood and country club pools. 25 yards - also known as “ short course yards” or simply “yards”.In the US, there are three commonly encountered lengths, or courses, for competition pools. Simply put, “swim course” is just a fancy name for a standard pool length. In this post, we explain all the acronyms and jargon, and dispel the mysteries and common misunderstandings around converting a swim time from one course to another. Yet, one topic that invariably trips up new swim moms and dads is the concept of “swim courses” like “SCY” and “SCM” and understanding why and how times are converted between them. Swimming is a fun and family-friendly sport.

Swim time converter